Undertow or rip current? Either way, swim with care

By JOHN PETRICK

STAFF WRITER |

The Record

Back in the old days, it was known as the "undertow," that dreaded phenomenon that could sweep ocean bathers in over their heads without a moment’s warning. "Watch out for the undertow!" your mom would always warn you.

associated press

Beachgoers walk past the area in Ocean City where a 14-year-old boy was swept out into the ocean by a rip current last month.

Today, it’s called the rip current.

Or wait. Is it the rip tide?

Actually, experts say, there’s a difference between the rip current, the undertow and the rip tide. Not to mention how they differ from what’s known as the rip channel.

Then there are those surf forces we don’t hear much about. Though given AccuWeather’s love for issuing advisories and warnings, rest assured that some day, you probably will. There’s backwash, breakers, feeder currents, littoral currents, head of rip, and, probably some day, tips on exactly what you should and shouldn’t do when faced with any given one of them.

Drowning in this sea of terminology? As the experts might advise you: Don’t panic. It’s all just a matter of being pulled down, or up, or in, or out. But as the Rip Current Advisory becomes as much a staple of the daily summer forecast as the ocean temperature itself, one has to wonder: Was it always this risky to go in the water? Or is the rip current just the same old undertow, with a new name and a lot more hype?

"The undertow is an actual thing, but it is separate and different [from] rip currents," said Jon Miller, professor of coastal engineering at Stevens Institute of Technology in Hoboken.

Miller is currently training a pilot group of lifeguards from Asbury Park, Bradley Beach and Allenhurst how to use an app he has helped develop that will gather and share their observations of rip currents daily. This will not only help them recognize any patterns that may emerge, but will help scientists like Miller accumulate season-wide data that might uncover what conditions make rip currents more prevalent or severe.

"The undertow is caused when the waves break and they push a whole lot of ocean up onto the beach. That water that hits the beach has to go back somewhere, so when it starts heading back out to sea, if you’re standing where the waves break, it is easy to be thrown off balance."

Contrary to popular belief, said the scientists, the undertow does not pull you under. It only tries to drag you out.

But isn’t that what a rip current does? Sort of — but in a different and much more powerful way.

"An undertow may feel like you are being sucked into the ocean, but the next wave will punch you right back into the shore," said New Jersey State Climatologist Dave Robinson. "The rip current is a more concentrated zone, almost like a little river. That’s where people can get into trouble really quickly — because it is such a fast current. Even the strongest swimmer will have difficulty if they try to swim opposite the current. Better to angle yourself out of the flow, and get away from it. And hopefully, someone is there to help you get back to shore."

Many use the misnomer "rip tide," which is technically incorrect, according to Josh Kohut, associate professor of oceanography at Rutgers University in New Brunswick. It’s "rip current." Not that you’ll be thinking about its proper label when you’re caught in the thick of one. "Your first reaction is to swim toward the beach – but that is the worst thing you can do. It’s like running into the wind. If that wind is very strong, you make no progress," he said. "The best thing to do is to swim parallel to the beach, to get out of the current. You don’t have to go very far – they’re pretty narrow."

Scientists say that while Superstorm Sandy, beach replenishment projects and other factors have altered the ocean bottom in some places, they haven’t done so in a way that should have made the surf any more treacherous now than, say, 20 years ago. It may seem like there are more reports of drownings and rip currents – but that’s just it. It’s more reports of them.

"A rip current is a natural process that has been around. I think it’s just the awareness that has increased, and efforts to make the public more aware of how to safely navigate it," Kohut said.

If anything, said Robinson, changes to the shore may have actually made the surf calmer.

"Sandy certainly rearranged not only the beaches and back bays, but it also did a job on the offshore bottom of the ocean," Robinson said. "But the other thing to look at is that beach replenishment has changed the contours of the beach and the offshore areas. To tell you the truth, I don’t know whether it’s exacerbated or reduced the threat of rip currents – or maybe done nothing. But I do know that surfers don’t like beach replenishment because it tends to streamline the onshore and offshore landscape, whereas they like to see more sandbars just offshore, because that helps the waves break better. Waves break as the ocean gets shallower. But beach replenishment levels things out."

Miller said that swimmers can try to avoid rip currents by being mindful of several things. Rip currents tend to occur more frequently and with more intensity during low tide, he said. Also, they are frequently found near structures like jetties. And, if there is a rip tide in a specific location one day, it will likely recur in that same location the next.

"The truth is very few people who get stuck in a rip current, when lifeguards are around, actually die. About 99 percent actually get rescued. The unfortunate thing is when people go swimming after hours or before lifeguards come in, in the morning. Or on the off-season," Miller said.

"Most people have been stuck in rip currents before. It’s just that not all are strong enough to pull you out. Most people have had that feeling where you suddenly just can’t get back in. It’s a momentary feeling of panic, and then you figure it out," he added. "Rip currents never pull you under the water. That’s the big misnomer. They pull you out into the ocean. Then people panic, expend all of their energy at once, and they sink," he said.

"It’s panicking and getting tired that pulls them under. The No. 1 rule is not to panic."

Back in the old days, it was known as the "undertow," that dreaded phenomenon that could sweep ocean bathers in over their heads without a moment’s warning. "Watch out for the undertow!" your mom would always warn you.

Safety tips

How to avoid and surviverip currents:

Don’t fight the current. Swim out of the current in a direction following the shoreline. When out of the current, swim toward shore.

If you are unable to swim out of the rip current, float or calmly tread water. When out of the current, swim toward shore.

Never swim alone.

Swim at a lifeguard-protected beach.

If caught in a rip current, remain calm to conserve energy and think clearly.

Avoid jetties and other sea structures, where rip currents are more prevalent.

Source: National Oceanic and AtmosphericAdministration (NOAA)

Telling the difference

Is today’s much-heralded "rip current" yesterday’s old "undertow," just renamed and with more publicity? Not really, according to scientists.

Undertow: After a wave breaks and runs up the beach, most of the water flows seaward. This backwash of water can trip waders, move them seaward, and make them susceptible to immersion from the next incoming wave.

Rip current: A relatively small-scale surf-zone current moving away from the beach. Rip currents form as waves disperse along the beach causing water to become trapped between the beach and a sandbar or other underwater feature. The water converges into a narrow, river-like channel moving away from the shore at high speed.

Rip tide: Often incorrectly used as the term for rip current, it’s a distinctly separate type of current that includes both ebb and flood tidal currents that are caused by egress and ingress of the tide through inlets and the mouths of estuaries and harbors.

Source: the National Oceanic and Atmospheric Administration (NOAA)

Today, it’s called the rip current.

Or wait. Is it the rip tide?

Actually, experts say, there’s a difference between the rip current, the undertow and the rip tide. Not to mention how they differ from what’s known as the rip channel.

Then there are those surf forces we don’t hear much about. Though given AccuWeather’s love for issuing advisories and warnings, rest assured that some day, you probably will. There’s backwash, breakers, feeder currents, littoral currents, head of rip, and, probably some day, tips on exactly what you should and shouldn’t do when faced with any given one of them.

Drowning in this sea of terminology? As the experts might advise you: Don’t panic. It’s all just a matter of being pulled down, or up, or in, or out. But as the Rip Current Advisory becomes as much a staple of the daily summer forecast as the ocean temperature itself, one has to wonder: Was it always this risky to go in the water? Or is the rip current just the same old undertow, with a new name and a lot more hype?

"The undertow is an actual thing, but it is separate and different [from] rip currents," said Jon Miller, professor of coastal engineering at Stevens Institute of Technology in Hoboken.

Miller is currently training a pilot group of lifeguards from Asbury Park, Bradley Beach and Allenhurst how to use an app he has helped develop that will gather and share their observations of rip currents daily. This will not only help them recognize any patterns that may emerge, but will help scientists like Miller accumulate season-wide data that might uncover what conditions make rip currents more prevalent or severe.

"The undertow is caused when the waves break and they push a whole lot of ocean up onto the beach. That water that hits the beach has to go back somewhere, so when it starts heading back out to sea, if you’re standing where the waves break, it is easy to be thrown off balance."

Contrary to popular belief, said the scientists, the undertow does not pull you under. It only tries to drag you out.

But isn’t that what a rip current does? Sort of — but in a different and much more powerful way.

"An undertow may feel like you are being sucked into the ocean, but the next wave will punch you right back into the shore," said New Jersey State Climatologist Dave Robinson. "The rip current is a more concentrated zone, almost like a little river. That’s where people can get into trouble really quickly — because it is such a fast current. Even the strongest swimmer will have difficulty if they try to swim opposite the current. Better to angle yourself out of the flow, and get away from it. And hopefully, someone is there to help you get back to shore."

Many use the misnomer "rip tide," which is technically incorrect, according to Josh Kohut, associate professor of oceanography at Rutgers University in New Brunswick. It’s "rip current." Not that you’ll be thinking about its proper label when you’re caught in the thick of one. "Your first reaction is to swim toward the beach – but that is the worst thing you can do. It’s like running into the wind. If that wind is very strong, you make no progress," he said. "The best thing to do is to swim parallel to the beach, to get out of the current. You don’t have to go very far – they’re pretty narrow."

Scientists say that while Superstorm Sandy, beach replenishment projects and other factors have altered the ocean bottom in some places, they haven’t done so in a way that should have made the surf any more treacherous now than, say, 20 years ago. It may seem like there are more reports of drownings and rip currents – but that’s just it. It’s more reports of them.

"A rip current is a natural process that has been around. I think it’s just the awareness that has increased, and efforts to make the public more aware of how to safely navigate it," Kohut said.

If anything, said Robinson, changes to the shore may have actually made the surf calmer.

"Sandy certainly rearranged not only the beaches and back bays, but it also did a job on the offshore bottom of the ocean," Robinson said. "But the other thing to look at is that beach replenishment has changed the contours of the beach and the offshore areas. To tell you the truth, I don’t know whether it’s exacerbated or reduced the threat of rip currents – or maybe done nothing. But I do know that surfers don’t like beach replenishment because it tends to streamline the onshore and offshore landscape, whereas they like to see more sandbars just offshore, because that helps the waves break better. Waves break as the ocean gets shallower. But beach replenishment levels things out."

Miller said that swimmers can try to avoid rip currents by being mindful of several things. Rip currents tend to occur more frequently and with more intensity during low tide, he said. Also, they are frequently found near structures like jetties. And, if there is a rip tide in a specific location one day, it will likely recur in that same location the next.

"The truth is very few people who get stuck in a rip current, when lifeguards are around, actually die. About 99 percent actually get rescued. The unfortunate thing is when people go swimming after hours or before lifeguards come in, in the morning. Or on the off-season," Miller said.

"Most people have been stuck in rip currents before. It’s just that not all are strong enough to pull you out. Most people have had that feeling where you suddenly just can’t get back in. It’s a momentary feeling of panic, and then you figure it out," he added. "Rip currents never pull you under the water. That’s the big misnomer. They pull you out into the ocean. Then people panic, expend all of their energy at once, and they sink," he said.

"It’s panicking and getting tired that pulls them under. The No. 1 rule is not to panic."